Schooling fish inspire new approach to wind farming

Schooling fish, it turns out, have a lot to teach us about setting up wind farms. That’s the conclusion reached by John Dabiri, a fluid dynamics expert from the California Institute of Technology (Caltech). One of the biggest current problems with wind farms is the large land area that they require - if you place the turbines too close to one another, they will be adversely effected by each other’s turbulence. By applying principles learned from observing fish, however, Dabiri thinks he might have found a solution.

First off, he is not using the common type of wind turbine. What we’re used to seeing are horizontal-axis turbines, with the big windmill-style blades that spin in a circle perpendicular to the ground. Dabiri is using vertical-axis turbines, that look not unlike an old-school lawnmower (or combine) reel standing on one end. Because they don’t have big blades sweeping circles in the air, they can be more densely-spaced than horizontal-axis machines.

One of the first things Dabiri noticed with schooling fish was that the vortices left behind individual fish sometimes rotated clockwise, and sometimes counter-clockwise. In traditional wind farms, all the turbines spin in the same direction, so they all generate the same direction of vortex. Based on this observation, he plans on alternating the spinning direction of neighboring turbines, to see if they actually benefit from the alternating vortices.

Dabiri also noticed that the fish and their vortices were arranged in a staircase pattern relative to one another. Again, this runs contrary to most wind farms, where the turbines are placed in neat rows. By conducting a field study incorporating closely-spaced, staggered vertical-axis turbines spinning in alternating directions, he hopes to show just how much more efficient wind power can become. According to Caltech's computer models, he believes his set up could be up to ten times more efficient than traditional models.

“Our goal is to demonstrate a new technology that enables us to extract significantly more wind energy from a given parcel of land than is currently possible using existing methods," said Dabiri. "We want to take advantage of constructive aerodynamic interference between closely spaced vertical-axis wind turbines. Our results can potentially make better use of existing wind farms, allow for wind farms to be located closer to urban centers - reducing power transmission costs - and reduce the size of offshore installations."

An experienced freelance writer, videographer and television producer, Ben's interest in all forms of innovation is particularly fanatical when it comes to human-powered transportation, film-making gear, environmentally-friendly technologies and anything that's designed to go underwater. He lives in Edmonton, Alberta, where he spends a lot of time going over the handlebars of his mountain bike, hanging out in off-leash parks, and wishing the Pacific Ocean wasn't so far away.

Isn\'t it ironic that most conventional renewable energy like wind, solar and hydro are all weather dependent? If we are to combat climate change with climate powered systems what happens when the climate changes? For that matter the biggest problem with wind and solar (not so much hydro) is that the weather doesn\'t always provide the energy when humans want to consume it. Maybe it would be more efficient if we would consume energy when and where its available...that would mean a change in lifestyle, but I think thats something we want and need to improve anyway.
Sustainability is a local action with a global impact and it starts at home.
Quite literally: Give the power to the people! (not the corporations...)

jeffbloggs

Jeffbloggs-

I agree with your opinion somewhat. Solar power( photovoltaics, thermal, ect), wind and tidal, can store energy by different kind of storing methods. Batteries, super hot salt(for solar heating systems; check out the one in Spain), hydrogen are few candidates.
These technologies are currently in use.

If scientists succeed in nuclear fusion, we could possibly solve all our energy needs for our
main electricity.

bio-power jeff

The vertical axis design has been tried and discarded. The problem is the cost of maintenance on the bottom thrust bearing carrying the load of the apparatus.

dchall8

Instead of waiting for solutions that may be viable, we need to use current technology to accomplish our climate, energy independence goals. We have choices, we can wait and see (what the climate will be like, or if technology is going to get better or whatever) till it\'s too late, or we can do everything we can now (even while enjoying the benefits like free energy from renewables) and know that we did our best. The icing on the cake is that we become more energy independent, spend less on energy, pay less taxes, and contribute to the betterment of technology and mankind. Can you tell I sell solar? I agree with Power to the People! Thanks for reading this.

Fabian Rousset

@ bio-power jeff
These systems are in use, this is true. Solar thermal is generally twice to three times more efficient than photvoltiacs and storing heat (in salt etc) is much less costly than storing electricity in batteries or hydrogen (most hydrogen is only a energy carrier not a source). Wind is also used in Europe to pump water up into Hydro for energy storage. These are all good ideas that will help reduce emissions and promote renewables.

One thing though: Nobody on the planet uses electricity directly, they all only use the effects thereof.

Electricity is a awesome carrier of energy and can easily and very efficiently convert to other forms of energy, but that is exactly my point: we only use every other form of energy, and consumption wise we use most energy for heating/cooling (or climate control!! ;) for which there are many locally available alternatives. For example heat recovery ventilation with proper building insulation standards, and 3m deep ground coupled heat pumps with CHP backup running off Biogas. See my explanation about biogas/methane in http://www.gizmag.com/electrode-materials-hydrogen-fuel/15118/

I believe the problem with climate change is a social one, not a technological one. We have the technology but there is a lack of willingness or incentive to use them. This is especially so if our lives are only focused on obtaining money (and the supposed power/security it provides) and as long as sustainability is considered costly, we will find it difficult to change.

You can paraphrase my above comment to: Nobody on the planet needs money directly, they all only use the effects thereof.

Maybe we should re-assess our goals and value systems to one that is based on the effects (products and services) rather that the accumulation of nearly 'worthless' paper. I sincerely hope we come to this realization before the rest of the unindustrialized world fully develops our predicament into the un-sustainability of mankind on the planet.

jeffbloggs

It doesn\'t matter if you can\'t store it. Any electricity generated from wind means that much less oil burned. If it\'s on your rooftop, you can either use it or sell it to the electric company for someone else\'s use, while you sit in your yard with a cold drink watching your electric meter wind backwards.

HenryFarkas

But if we really wanted to live within our power needs then most of our homes would be under ground!!!!
I\'m all for making the power where it is needed and used... but it amazes me to go to the worst places to live on earth i.e. apple valley CA and all you\'ll find are victorian style homes :(
We can do a lot better and really need to live within our power availability... that is the power we can make at home :)

Fetcher

I am not surprised by the staircase idea at all. Migrating birds use this principle to form their V shaped flights.

@jeffblogs - you can paraphrase your statement into a need for socialism or communism - hardly a practical solution, or an original one. Your last comment is rather rude: the \"unindustrialized\" world didn\'t get us into this situation, the industrialized world did - you\'re going to blame the third world for this as well now? I think you should re-assess YOUR goals and value systems...

GavinC

The helical style wind generators have a number of advantages including being less dangerous for birds (they seem to avoid it more than the large propeller blades) and they self-regulate their speed because they can be designed so that cavitation occurs above a critical velocity (just like a propeller in water).
I wonder whether the thrust bearing stress issue could be reduced by placing them horizontally. They would look even more like a \"reel\" lawn mower.

kwalker

@GavinC
A bit of a late response to your comment (ahem):

I am not blaming the third world at all for our predicament, I'm blaming the industrialized world for promoting systems and ideas that are unsustainable. This includes money, fossil fuel, political systems, economics and even pseudo science that is motivated by greed and control. Mob rule like democracy is not effective to identify the best way forward, as it is mostly driven by temporal motivations and emotions, not considered and factual debate that leads to sustainable planning.

My point was that we should develop something sustainable before we try to "force" (economically, politically, war, ideas) our "wicked" ways on the third world for them to adopt and make the destruction of the planet "complete" because they believed our current warped ideas were the solution. Everything man has ever done or made was once an idea. Lets' only promote sustainable ones.